#include<iostream>
using namespace std;

class Data
{
public:
	Data(int year, int month, int day);
	void print();
	bool operator==(Data cut);
	bool operator<=(Data cut);
	Data& operator+(int cut);
	Data& operator-(int cut);
private:
	int _year = 1;
	int _month = 1;
	int _day = 1;
};